It said it completed successfully

The instant that the upgrade has been applied, and the wizard is finished, run that Hyperterminal profile. Quickly! When the player reboots after the upgrade, you will see it reboot and it will start formatting the disk. You should see the formatter's output in ASCII on the serial port and on the screen of the player.

If the disk drive wasn't blank, the formatter may complain by saying 'disk is already built'. If this happens, you must prune the "fids" folder from the disk and apply the builder image again from scratch. Here is how to do that:

While still in Hyperterminal, get to a shell prompt. There's a chance that you might already be sitting at a shell prompt. If not, press ctrl-C and it should drop you to a shell. If not, see if sending a break command works (should be somewhere on the terminal program's menus).

type rwm (then press enter and wait a while for a shell prompt to appear)

type rm -r /drive0/fids (then press enter)

type rom (then press enter)

If everything worked, then pull the player's power, close Hyperterminal, and restart the procedure as described above, applying the builder image and launching Hyperterminal as soon as it's been applied, to make sure it didn't stall again a second time.

Eventually, it will complete the formatting of the disk. If you're using a factory builder, it will start a disk stress-testing loop at this point. (Note: Mark Lord's Bigdisk Builder does not do a stress testing loop.)

What exactly said it completed successfully?

That's your problem. "normal player firmware" cannot handle big drives (anything over 128GB). You *must* use a Hijack-based firmware package with that drive.

Redo the builder again, and then install a hijack-based firmware package directly afterwards, watching carefully for error messages and the like.